Metal sheet fabricating machine



Feb-20,1940. Y J.J.M 'NQFSKY 2,191,433

METAL SHEET FABRICATING MACHINE I FiledDec. s, 1938 s Sheets-Sheet 1 vINVENTOR JOH/Q J I72AA2OFSKY V O NEYS Feb. 20, 1940. J. MANQFSKY2,191,433

METAL SHEET FABRICATING MACHINE Filed Dec. 5, 1938 s Sheets-Sheet 2 fl mI g //%\\I v INVENTOR ,1 J. J. MANOFSKYV" 2,191,433

METAL SHEET- FABRICATING MACHINE Filed Dec. 3, 1938 3 Sheets-Sheet 3INVENTOR JOH/Z v z/v2 OF'SK Patented Feb. 20,1940 7 c v i c UNITEDSTATES PATENT OFFICE:

John J. Manofsky, Warren, Ohio, assignor to National. Gypsum Company,Bufialo, N; Y.

- Application December 3, 1938', Serial No. 243,809" 14' c aims. .(Cl.164-65) This invention relates to a machine for fabri- In thedrawingsthe numerals 10- and H des eating metal sheets and particularly to meansign'ate base members disposed at the feed and therewith for engagingsuch sheets for purposes discharge ends of the machine-respectively. Anof positioning and moving them. intermediate base member (not shown) ispref- The. invention may be advantageously employed erably provided.Extending 'between'the base 5' in the production of expanded metal lath.Ac members and H are spaced be s l3 a cording to the generally acceptedmethod'of prothe construction and operation of which will beducing-expanded metal lath a sheet of metal is hereinafter'described. aI

first provided throughout'a large part of its sur- The base l0 servesas'a support for forming i 10 face with a plurality of parallel slits,usually roll mechanism which is not shown in detail 0 extendinglengthwise of the sheet, and the sheet since such forming roll mechanismis conven' is then gripped at its opposite longitudinal edges, tionallyfound in machines of the kind under contransversely of the .extent ofthe slits, and sideration and the forming-roll mechanism entersstretched so that the slits open'up to form a into the present inventiononly insofar as it promesh. I f .duces sheets of a certain form forintroduction The machine of the present invention is deinto theexpanding mechanism. 1 signed to effect the stretching of thesheet; or IActuation of the entire machine may be effected expanding as it isgenerally known in the art, in by means'of an electric motor l5 whichengages an improved manner by providing a machine a conventional speedreducing unitflS through which is adapted to grasp the edges of thesheet the medium' of a flexible coupling [1. A drive 20 in a moreeiiicacious manner than has heretoshaft l8 extends longitudinally of themachine fore been the case. i and is jou'rnaled at one end'in bearingsl9 and Further advantages of the use of my improved 20 carried by thebase Ill. The other end of the metal sheet expanding machine and theimproved drive shaft 18 is journaled in a bearing 2| which sheetengaging means will appear from a study "in the drawings is supported bya pedestal 22. 25 v of the drawings and the following description.Disposed upon the right hand end of the base vIn the drawings: I memberIn as viewed inFigs. 1 and 2 isanele- Fig. 1 is a general plan view ofthe machine ment 23"having a flat top which serves as a tawith partsbroken away; bleupon which previously "slit work sheets are v Fig. 2 isa general side elevational View of the placed for introduction to themachine. I 30 machine, also with parts brokenaway; Adjacent the tablemember 23 are a pair of Fig. 3 is a cross sectional. view' takenapproxispaced b members 24 and 25 which are mately on the line. III-IIIof Fig. adapted to give support to a plurality of forming 4 is a P p vew f Several of the rolls. The forming rolls themselves are notinsheet gp elements s ow h in op n and cluded in Fig. 1 of the'drawings but theirnumin pp position; i 1 her and disposition is' adequately indicated, for5 is an enlarged elevational View of the the'purpose ofexemplificatiomin Fig. 2, where entrance portion f the pa n mechanismthe journals of two pairs of rolls, 25, 21 and 28. showing the gripperclosing device; 29,'with their associated bearing blocks, appear.

40 Fig. 6 is a plan view of that portion of th The two' pairs of rollspreferably constitute two machine; v passes wherein grooves extendinglongitudinally Fig s an elevational V Of e delivery ofthe work sheet areformed. Thesegrooves are p n f the pa n nism sh wing t primarily formedin the work sheet tolend added pp r ClOSing device; stiffness to theultimate product and for other 46 8 s a p an w Of at p n of thestructural reasons, but utilization of their presmachine; ence in theunexpanded work sheet is made to Fig. 9 is an end elevational view, alsoof that the end that the work sheet may be securely and a portion of themachine; and efiicaciously clamped during the expanding op- I Fig. -1Ois a diagrammatic view showing aperation'. 50 proximately the appearanceof the work sheet The work sheet is impressed, in its passage be- 50 incross section as it is delivered to the expand tween the forming rolls,with a number of loning mechanism. gitudinally extending V-shapedcorrugations. n Fi s. 1 and 2 the cent al part of the ma- One suchcorrugation will appear-along each chine has been broken away to permitillusmarginal edge .and one or more corrugations may tration on a largerscale. occur at medialv points'across the sheet. In the 55 presentinvention we are immediately concerned ride between upper and lowerpairs. of .guide bars I which engage the marginal corrugations. The

upper guide bars are designated at 36, and the The guide bars are 'so'lower guide bars at 37. arranged that they diverge. in a direction awayfrom the forming roll mechanism and in a horizontal plane. Thisdivergence is for a purpose which will hereinafter appear.

Bracket ill is either secured to or formed upon the pedestal or basemember llland gives support to one end of eachof the beams'l3 and I4,their other ends being, as previously stated, disposed upon the otherbase member An intermediate'pedestal or base member is preferablyemployed but this is done for added strength only, does not vary theoperation of the present invention, and has not been illustrated in thedrawings, being brokenaway in Figs. 1 and 2. As may be noted in the planview, Fig. 1, the beams l3 and i i are substantially divergent in adirection away from the forming rolls which are carried by the basemember if]. i

In Fig. 3 the cross section of the left han beam I3 is shown taken atsome intermediate point and the cr'oss section of the right hand beam Mis taken adjacent its end where it gives support toa sprocket wheel 4!.Similar sprocket wheels are provided in association with each end ofeach of the beams l3 and [4. The sprocket wheels at the ends adjacentthe base member I!) are disposed for idling rotation upon the stubshafts which are journaled in the beams I3 and M as is shown in Fig.3..

The sprockets at the other ends of the beams l3 and i i are connectedfor joint rotation by a shaft 44, see Fig. 1, a pair of conventionaluni-- versal joints 45 and 46 being interposed because each of thesprockets rotates upon an axis at right angles to its associated beamand the pair of sprockets at each end of the machine are consequentlynot coaxial.

One of the sprockets at the left hand end of the machine as seen inFigs. 1 and 2 is connected to the drive shaft l8 by means of a pair ofbevel gears W and 4t. 7

The chain which is associated with the sprockets 4! is of specialconstruction and forms an important part. of the present invention. Thechain is shown in cross section in Fig. 3 and several links of the chainare shown in perspective in Fig 4. The chain resembles. a driving chaingenerally in that it is provided with pairs of side links 56 and centerlinks 5| which pivots ally connect each pair of side links with anadjacent pair of side links by means of pivot pins 52. The center links5!, however, are in the present invention of novel form and embody'meansfor selectively clamping the edges of work sheets in a manner which willappear from the following description. 1

Each center link M has rigidly associated with it a hardened steel block53 having a corrugated upper surface, which corrugations are formed tomatch the under surface of the corrugated edge of a work sheet such asthe one illustrated in Fig. 10. The block 53 may be satisfactorily heldin assembly with the center link 5| by the pivot pins 52 which extendthrough the side and center links 50 and 5| respectively.

An upward extension of each center link 5| is formed to provide a pairof aligned bearings 54, which, throught'he mediurnjof a bearing pin 55which extends lengthwiseof the chain,'pivotally supports a movableelement 58, the movable element being provided for this purpose with asuitable bearing portion 59. In Fig. 4 two such movable elements 58 areshown, the first one from the left being open and the second from theleft being inclosed or clamping position.

Each movable element 58 has secured thereto or therein an insert 60,preferably of hardened steel, which has a downwardly disposed V-shapedprojection which is complementary with respect to the corrugated block53 and is adapted to cooperate therewith to engage and clamp thecorrugated edge of a work sheet when the movable element is in theposition shown at the right of Fig. 4.

Spaced upwardly extending bearing portions 6| are furtherprovided uponthe movable element 58 and between them. a roller '62 is rotatablydisposed. The bearing pin 63 for the roller has a projection 65 whichserves as a sort of cam follower in the opening and closing movements ofthe elements 58in a manner which will hereinafter appear. The purposeand function of the roller 62 which is associated with each movableelement 58 will also become evident further on in this specification.

The sprocket wheels 4|, which for simplicity are not shown in elevationin the drawings, are of usual construction with teeth which fit andenter the openings in the chain. These openings lie between eachadjacent pair of center links BI and are further defined by eachcooperating pair of side links 50.

The beams IS and Hi have in their upper surfaces longitudinallyextending grooves or channels 66 which, in the illustrated embodiment,extend the entire length of each beam. -The lower or relativelystationary portions of the chain, comprising the side and center links,are adapted to travel in this channel and be guided by the wallsthereof. To avoid the necessity for replacing the beams when wear occursas well as to facilitate accurate manufacture in the first instance,lower and side wear plates or blocks in and H respectively arepreferably disposed in the channel'68.

, An elongate element 12 of overhanging cross section is fixed along thetop of each of the beams l3 and 14 as by screws 13. The overhangingportion M of each of these elements is so located as to overlie itsassociated chain and means are provided on the former for engagementwith the latter for the purpose of keeping the clamping.instrumentalities in closed, or clamping position during certain periodsof operation. To further this objective a longitudinally extendingpressure bar 75 is associated with the under side of each overhangingportion 14 and in the illustrated instance is set into a longitudinalgroove 16 provided therefor in the overhanging portion Screws Tl aredisposed in apertures in the overhanging portion 14 and their threadsengage the bar 15. The screws I? have free axial sliding movement withrespect to the overhanging portion 11 and their length is such that whenthe bottom of'the pressure bar 15 surrounds the shank of each screw-11,bear.- ing at its lower end against the top of the pressure bar 15' andat its upper end against the bottom: of aheadless screw 8| which isthreaded into the overhanging portion 14.

By the means described th'e'pressure bar is caused to exert a resilientdownward pressure upon the rollers 62 as they pass therebeneath andthereby hold the movable elements 58 of g the chain in closed positionwith the edge of a work sheet securely clamped thereby.

The general scheme of operation of the present invention is as follows.The work sheet, after having the edge corrugations formed therein in theforming roll unit carried by the base H! as has previously beendescribed, emerges therefrom and passes to the chain. means where theedge corrugations of the sheet pass onto andin chains at the oppositesides of the machine, in their travel from the sprockets '4! at theforming roll end of the machine to the sprockets at the delivery end ofthe machine, the previously slit work sheet whichis held at its edges bythe clamp ing means of the chain links is caused to 8X- pand in thedirection of its width, in a manner well understood in the art, 'to forma sheet of expanded metal lath.

Adjacent the delivery end of the machine further automatic means areprovided for opening v the clamping means associated with each chainlink successively as-tl'iey reach such automatic means and the means ateach end of the machine for so automatically closing and opening theclamping means will now be described.

Figs. 5 and 6 are fragmentary elevational and plan views respectively ofthe portion of-the ex-- pan'ding mechanism which lies adjacent theforming roll mechanism and which first receives the work sheettherefrom. For simplicity'neither the chain itself nor the sprocket isshown in these figures. An endof the beam I3 is shown and associatedtherewith the sprocket shaft 42. A semicircular cam ring is supported insubstantially-concentric relation with the sprocket and sprocket shaft42 by brackets 86 secured to the ends of the beam l3. s

The cam ring 85 is of generally uniform thickness in the direction ofits radius but its lower portion is thinner at the outside, forming theangularly disposed cam face 81 which merges with the inner trulycircular face 88 of the cam ring and at its upper end the cam ring isthinner at the inside as is indicated by the dotted line 89 g to form anangularly disposed cam face which is opposite in inclination to thelower cam face portion 81. i

As the lower reach of the chain, indicated in dot and dash lines at 84in Fig. 2, approaches the cam ring, in a direction'from left to right asseen in Figs. 5 and 6, the movable elements 58 of the chain occupyapproximately the position shown in" the lower right hand corner of Fig.3, being so disposedv by the force of gravity. The chain link moves intocontact 'withthe cam ring with the radial face at the end of thefollower pin 64 riding against the angularly disposed portion 81 of thecam face.

As the chain moves about the sprocket the cam-contacting face at the pin'64 reaches'the flat portion 88-'of the cam face. and the movableportion 58 of the chain link is consequently held in the position shownat the left of Fig. 4, that is, in a position where it has beenpivotally moved through ninety degrees from a fully closed position.Subsequent to this opening movement of theelement 58 the lateral face ofthe'element 58 which lies opposite the pin' 64' passes into contact withflat upperface 90 at the extremity of a bracket 9|. 1 Such lateral faceof the element 58 is indicated at in the lower right hand corner of,Fig. 3. I

fIhebracket 9| may be'secured to the end of the element 12 as bymeans ofthe screw 92-and the bracket has an inner vertically extending portion93, the bracket bein'g twisted so that the inner vertically extendingportion merges into the outer somewhat horizontally extending portion.The relieved surface of-the cam ring 85 indicated by the dotted line 89is really only for clearance since the pivotal movements ofthe movableelement 58 are controlled by the cam bracket 9! as soon as the flat face95 of the movable element 58 rides onto the flat extremity 90 of thebracket 9|. I

As the chain link progresses the contact of the cammingface of thebracket 9| with the portion 95 of the element 58 rotates the'movableelement throughninety degrees to the closed position indicated at thetop of Fig. 3, the work sheethaving by thistime been fed onto the lowerclamping elements 53 of the chain. The chain links then pass-beneath theoverhanging portion 14' of the element 12 where the rollers 62 areengaged by the pressure bar 15in a maner which has previously-beendescribed. To simplify the drawings, the'clamp closing instrumentalitiesof Figs. 5 and 6 have been omitted from Figs. 1 and 2.

After the chains have traversed the entire length of the diverging beamsl3 and-l4 and as each link is about to engage its associated sprocket atthat end of the machine, it is engaged by cam..-

of each element 12 and having a flat extension thereon which isdisposed'vertically adjacent its base portion as at 99 and which istwisted out-- wardlyso that at its extremity. it extends almosthorizontally as at I90.

As may be seen from an inspection of Fig. 9,

there is a notch llll in the bottom of the fastening flange of'thebracket 98 through which each link passes as it emerges from beneath theoverhanging portion 14 of I the member 12. In so emerging the radialface of the pin 64 of each I movable element 58 of a chain link comesinto cammingxcontact with thesubstantially vertically extending portion99 of the cam bracket 98. It will be obvious that further forwardmovement of the link will,&by virtue of the camming action of theportions 99 and I80 of the cam bracket 98,. cause the movable elements58 of the successive links to be pivotedqto an open or non-clampingposition, whereupon the work sheet =moves out of contact with thegripping means at the sprocket. and continues its forward motion in. a

straight line as the chain elements follow each other around thesprocket.

I find that highly successful operation results when the sprckets aredriven at a speed which gives to the chain elements a surface speedwhich is approximately two per cent greater than the surfacespeed'imparted to the work sheets by the forming roll mechanism. Thisdifference results in some slipping of the work sheet in the clampingmechanism but gives to the work sheet while in the clamping mechanism alengthwise tension which results in a much improved final product andone. which islfree from troublesome surface irregularities which havelong been a problem in producing; expanded metal lath.

It will be noted that the work sheet is gripped by an actual mechanicalinterlock so far as its transverse dimension is concerned but isonlyfrictionally gripped in the direction of its'length. This system ofgripping permits the aforementioned sheet tensioning to be accomplishedwith facility and without reducing the certainty of gripping in thedirection of the width of the sheet where, of course, the tensile stressis by far'the greatest and where any slipping will result in animperfect product.

While a single preferred embodiment of my invention has been illustratedit is not to be considered that my invention is limited thereby or inany other way save as defined in the appended claims.

What is claimed is:

1. In a machine for producing expanded metal sheets, chain means forgripping and conveying pre-slit work sheets having longitudinallyextending marginal corrugations, said chain being made up of alternateand pivotally connected center links and pairs of side links, saidcenter links each having a body portion pivotally connected to adjacentside links at each end thereof and a second portion movably associatedtherewith, said body portion and second portion cooperating toselectively clamp or release a work sheet by interlocking engagementwith the marginal corrugations thereof. a

2. In a machine for producing expanded metal sheets from pre-slit worksheets having longitudinally extending marginal corrugations, a pair ofgripping and driving chains arranged in spaced relation for cooperationone with each longitudinal edge of the work sheet and a pair ofsprockets associated with each chain, said chains extending in divergingdirections whereby a work sheet is compelled to assume a constantlyincreasing width as it is moved along by said driving chains with its'opposite longitudinal edges;

engaged thereby, eachof said chains comprising alternate side and centerlinks pivotally interconnected with their pivotal axes extendingparallel to the axes of their associated sprockets, some of said linkshaving clamp-ing elements movably associated therewith for pivotalmovement along an axis extending parallel to the path of said chain andadapted to cooperate with their associated links toengage the marginalcorrugation of the work sheet and thereby'form releasable clamps.

3. In a machine for producing expanded metal sheets from work sheetshaving longitudinally extending marginal deformations, a pair ofgripping and driving chains arranged in spaced relation for cooperationone with-each longitudinal edge of the work sheet and a pair ofsprockets associated with each chain, said chains extending in divergingdirections whereby an engaged work sheet is compelled to assume aconstantly increasing width as, it is moved along by said drivingchains, each of said chains comprising a plurality of link elementsinterconnected for pivotal movement about axes extending parallel to theaxes of their associated sprockets, some of said links having clampingelements movably associated therewith for pivotal movement along an axisextending substantially parallel to the path of said chain and adaptedto cooperate with their associated links to-engage the marginaldeformationof the worksheet and thereby form releasable clamps.

4. In a machine for producing expanded metal sheets, a pair of grippingand driving chains arranged in spaced relation for cooperation one witheach longitudinal edge of a work sheet having pre-formed marginalcorrugations and a pair of sprockets associated with each chain, saidchains extending in diverging directions whereby an engaged work sheetis compelled to assume a constantly increasing width as it moves alongby said driving chains, each of said chains comprising a plurality ofinterconnected link elements, some of said links having clampingelements movably associated therewith for pivotal movement along, anaxis extending parallel to the path of said chain and adapted tocooperate with their associated links to form releasable clamps forinterlocking engagement with the marginal corrugations ofthe worksheet,guide means extending along one reach of each of said chainsfor engagingsaid-chains when said means 'are in clamping relation, said guide meanshaving opposed ,faces for engaging opposite sides of the stationary andmovable portions of the clamping links to confine such stationary andmovable portions and thereby prevent their separation duringsubstantially the entire period of the passage of the sheet between saiddiverging chains.

5. In a machine for producing expanded metal sheets from pre-slit worksheets having longitudinally extending marginal corrugations, a drivingchain for said sheets comprising a series of links successivelyinterconnected for pivotal movement about axes extending at right anglesto their line of travel, some of said links, having corrugations intheir upper faces extending in the direction of travel of said chain andadjacent thereto pairs of spaced coaxial bearing portions havingtheircommon axis extending in the direction of travel of said chain, amovable element having a bearing portion disposed between each such pairof spaced bearing portions. a pivot pin connecting said movable portionwith its, associated link for pivotal movement, the under face of saidmovable element having a face which is complementary with respect to thecorrugations in the-upper face of said link and the formation of bothsaid faces being such as interlock with the marginal corrugation of awork sheet when said movable element is pivoted to bring its lower facetoward the upper surface of its associated link.

'tionswith. their common axis extendingisubstantially in the directionof travel -ofsaid chain, a movable element having a bearing portiondisposed between saidspaced bearing portions, and I driving chain forsaid sheets comprising aseries of longitudinally overlapping linkssuccessively I interconnected for pivotal movement about axes extendingat right angles to their. line of travel, altemate links beingsubstantially contiguous owing to said overlapping-arrangement and eachalternate link having spacedcoaxial bearing portions with their commonaxis extending substantially in the direction of travel, of saidchain, amovable element having a bearing portion dis-.

posed between said spaced bearing portions, and

a pivot pin connecting said movable element with the bearing portionsofits associated link for pivotal :movementsaid movable element and itsassociated link having complementaryopposed longitudinal corrugationsfor fin aging the upper and under sides respectively of the marginal portion of said work sheets for interlocking engagement with themarginalcorrugations thereof, the corrugation of said link extending sustantially the full length thereof and the corrugated portion of saidmovable element being of substantially the same length assaid linkwhereby the work sheets are 'interlockingly engaged along a majorportion of their longitudinal. extent when in engagement with said chainmeans. l

8. In a machine for producing expanded metal sheets from pre-slit worksheets having longitudinally extending marginal corrugations, a drivingchain for said sheets comprisinga series of links successivelyinterconnected for pivotalmovement about axes extending at right anglesto their line of travel, some of said links having corrugations in theirupper faces extending in the direction of travel of said chain andbearing portions having an axis extending substantially parallel to saidcorrugations, movable elements associated with said bearing portions forpivotal movement with respect to said links, the under face of eachmovable element having a face which is complementary with respect to thecorrugations in the upper face of itsassociated link and the formationof said upper and lower faces being such as to interlock with'themarginal corrugation of a work sheet when said movable element ispivoted to bring its lower face toward the upper surface of itsassociated link.

9. In a machine for producing expanded metal sheets from pre-slit worksheets having longi tudinally extending marginal corrugations, a drivingchain for said sheets comprising a series of links successivelyinterconnected for pivotal movement about axes extending at right anglesto their line of travel, some of said links having corrugations in theirupper faces extendingin the direction of travel of said chain andbearing portions havingan axis extending substantially parallel to saidcorrugations, movable elements associated with saidbearing portions forpivotal movement with respect to said. links, the under face of eachmovable element having a face which .is'complementary with respect tothecorrugations -in-the upper face of its associated link and the formationof said-upper and lower faces being such as to interlock with themarginal corruga tion of a worksheet when saidmovable element is pivotedto bring, its lower face-toward the upper surface of its associatedlink, a longitudinally extending track upon which the chain is;'suported and an overhangingportion associated therewith, andanti-.frictionmeans at the upper side of said movable elements forcontact with the under face ,ofisaid overhanging portion to insurepositive interlocking between said links, 'fsaid movable elements, andthe marginal corrugations of 1 said sheets during the passage of thechain along said track, 1 n

- Y :10. In a machine. for producing expanded metal 2 sheets from'pre-slit "work sheets having longitudinally extending. marginalcorrugations, a

drivingchain" for said sheets comprising a series of. links successivelyinterconnected for pivotal movement. about axes extending at rightanglesto their line. of travel, some of "said linkszhaving corrugationsiintheir upper faces extending in the direction of travel of said chain andbearing portions havinganaxis extending substantially,

parallel-to said corrugations, movable elements associated-with saidbearing portions for pivotal movement with respect to said links, theunder face of each movable element having a face which is.complementarywith respect to the corrugations in .theupper face of itsassociatedlinkand .the formation .of said upper and lower faces beingsuch asto interlock withthe marginal corrugation of. a work sheet whensaid movable element is pivoted to bring its lower face toward the uppersurface of its associated link, a longitudinally extending track uponwhich the chain is supported, and resilient means: associated therewithand disposed to overlie said chain and engage the upper portion of saidmovable elementsto resiliently maintain associated links and 'movableelements in interlocking engagement with the marginal corrugations ofsaid sheet.

; 11. In a machine for producing expanded metal sheets from pre-slitwork sheets havingrlongi- 1 tudinally extending marginal corrugations, a

driving chain for said sheets comprising a series of links successivelyinterconnected for pivotal movement about axes extending at right anglesto their line of travel, some of said links having corrugations in theirupper faces extending in the direction of .travel of said chain andbearing portions having an axis extending substantially parallel to saidcorrugations, movable elements.

associated with said bearingportions for pivotal movement with respectto said links, the v under face of each movable element having a facewhich is complementary withrespect to the corrugations in the upper faceof its associated link and the; v

formation of said upper and lower faces being such as to interlock withthe marginal corruga-' tion of a work sheet when said movable element ispivoted to bring its lower face toward the upper surface of itsassociated link, a longitudinally extending track upon which the chainis supported'and resilient means associated therewith and disposed tooverlie said chain, and antifriction means associated with each ofthemovable elements and adapted to be engaged by said resilient means,said track and said resilient means cooperating to maintain associatedlinks and movable elements in interlocking engagement with marginalcorrugations of said sheet during the passage of the chain along saidtrack.

12. In a machine for producing expanded metal sheets from pre-slit worksheets having longitudinally extending marginal corrugations,

a driving chain for said sheets comprising a series of linkssuccessively interconnected for pivotal movement about axes extending atright angles to their line of travel, some of said links havingcorrugations in their upper faces extending in the direction of travelof said chain and bearing portions having an axis extendingsubstantially parallel to said corrugations, movable elements associatedwith said bearing portions for pivotal movement with respect to saidlinks, the under face of each movable element having a face which iscomplementary with respect to the corrugationsin the upper face of itsassociated link and the formation of said upper and lower faces beingsuch as to interlock with the marginal corrugation of a work sheet whensaid movable element is pivoted to bring its lower face toward the uppersurface of its associated link, a longitudinally extending track uponwhich the chain is supported and an overhanging portion associatedtherewith, said overhanging portion contacting said movable elements andcooperating with said track to maintain positive interlock between saidlinks, said movable elements, and the marginal corrugations of saidsheet during the passage of the chain along the track, and meansdisposed at opposite ends of said track for moving each movable elementinto interlocking engagement with its associated link and the work sheetprior to its entry upon the track and for releasing each movable elementfrom such interlocking engagement upon its exit from said track.

' 13. In a machine for producing expanded metal sheets, means forforming marginal longitudinally extending corrugations, said meansincluding means for feeding-said sheets through said forming means at apredetermined rate of speed, mechanism for expanding said sheetsincluding a driving chain for receiving said sheets from said formingmeans and for moving the same through the expanding mechanism byfrictional engagement and means interrelating said feeding means andsaid driving chains to cause the latter to move faster than the formerby a predetermined fractional amount whereby predetermined longitudinaltension is imparted to said sheets upon entry to the expandingmechanism.

14. In a machine for producing expanded metal sheets, means for formingmarginal corrugations, said means including means for feeding saidsheets longitudinally through said forming means at a predetermined rateof speed, means for expanding said sheets including driving chains forreceiving said sheets from said forming means and for moving the samethrough the expanding means, said driving chains having complementarygripping elements adapted to engage the upper and lower sides of saidsheets at said marginal corrugations whereby said sheet isinterlockingly held in a-transverse direction and frictionally held inits longitudinal direction, means for interrelating the driving speedsof the drive means associated with the forming mechanism and the drivingchainsto cause the latter to move faster than the former in apredetermined degree whereby predetermined longitudinal tension is iimparted to said sheets upon entry to the expanding mechanism.

' JOHN J. MANOFSKY.

